| 摘要 |
<p>A vehicle brake master cylinder has in addition to the usual seal (11) near the rear end, a second seal (14) which is disc-like and located in a groove (10), the cross- sectional radial height of the seal (14) being in the range 2 to 10 times greater than the cross-sectional axial width, this second seal serving to prevent air entering the cylinder during rapid return of the piston (3). The sealing surface of the second seal may be barrel- shaped, and at least one supporting ring (15) may be provided. <IMAGE></p> |
